A wide variety of substances are or may be entrained in fluid, such as air, for study including, for example, cotton fibers, polyester fibers, other textile fibers, coffee, other particulate foodstuffs, etc. Such entrained material nearly always contains foreign matter, such as trash in cotton, and interesting variations in the material itself may be present. In cotton, tangled balls of fibers called neps, as well as trash, are interesting because both affect the utility and value of the cotton. In polyester fiber, foreign and undesirable entities known as shot or fused fibers, as well as neps, are interesting because these entities also degrade the performance of the raw material.
One device that measures such air entrained entities including neps is sold under the trade name AFIS by Zellweger Uster, Inc. In this device, a sample of entities, such as cotton fiber containing neps and trash, are fed to the machine, individualized, entrained in an airstream, and optically measured. While such devices work well to measure such things as neps in a cotton sample, it would be desirable to have fast and economical methods or devices to supplement, verify and/or calibrate the data produced by the AFIS device. In this application, it is highly desirable to establish a time relationship with the AFIS data event and the location of the entity on the physical nep. Another area of application is to directly monitor such foreign matter entities, without a separate optical measure. A final area of application is to monitor the main component of the sample itself, such as individual fibers.
More generally, the objectives of this invention are to topologically map the locations of entities in space and/or time, to map their locations in space with data events in time, or to map between different data events.
Topology, among other things, deals with mathematical relationships between points on general surfaces. In this invention we are concerned with entities such as neps or trash particles or fibers which comprise volumetric fiber samples within which it is impractical or impossible to "see" or examine them without interference; that is, it is impractical or impossible to measure them. We are concerned with presentation; this means transforming or mapping volumetrically-located entities onto surfaces or into lines where they can be measured substantially individually and thus without interference. The transformation leaves the entity properties substantially unchanged, or invariant.
Thus a first application of topological mapping is presentation of a volumetric sample of entities onto surfaces or onto lines wherein their presentation enhances or enables measurement. This mapping is described by the general transform operation EQU S.sub.v .revreaction.S.sub.s ( 1)
where S.sub.v describes each entities' location in the volumetric sample and S.sub.s describes its location when presented for measurement on a surface. This surface is called PHYSICAL MAP of the entities. The locations can be time-dependent.
Further to this objective of topological mapping, we establish the functional relationship of surface-located entities to measurement data events E(t) EQU S.sub.s (t).revreaction.E(t)
where E(t) is an n-dimensional vector, EQU R(t)=[V.sub.1 (t), V.sub.2 (t), . . . V.sub.n (t)], (2)
where the elements V.sub.1 (t) are physical responses such as voltage, force, time, etc.
The terminology "event" relates, for example, to a voltage waveform in time. Time need not be explicit, however, in Equation 2. The measurement data for the entities is called a DATA MAP.
It can be now appreciated that examination of the physical map of entities in concert with the data map is most useful. One may investigate relationships between events and entities or between events in two or more data maps or even between entities on two or more physical maps.
The physical and data maps can, for simplistic convenience, be planar or to the same scale. Both serve archival purposes. Modern computational methods and apparatus enable high-powered analytical investigations of relationships between mapped entities and events. In providing for apparatus and methods to meet the topological mapping objectives of this invention, a powerful new analytical tool is enabled.
There follow clarifying comments. Let the mappings be (1) the ordered individualization of entities such as fibers, neps and trash in bulk fiber samples, one at a time, followed by (2) measurement of these individual entities, followed next by the (3) presentation of all sample entities in serpentine tracks on planar mesh and (4) concluded by measurement of the entities when so preferably presented for examination.
A unique spatial relationship is provided between the location of the entities in the original volume and their position in the tracts (or along a line). A unique relationship is provided between the locations S.sub.s (t) of the spheres and entities on the physical map and their data events E(t). These mapping relationships are useful in themselves but we have special interest in relating the temporal measurement events E.sub.2 in Step 2 with those in Step 4, E.sub.4. We are topologically relating two data maps to investigate the data relationships for each entity removed from the volume sample (Step 1) and presented in the preferred planar pattern (Step 3).
To further simplify, assume that Step 4 is a reference method such as optical microscopy. We seek to relate these data to the event data of Step 2. This will be appreciated as a calibration procedure.
The data events and maps in either Steps 2 or 4 may be one dimensional, such a peak voltage for each nep, as in an AFIS sensor; two dimensional, such as charge-coupled signals representing images of a trash particle; or three-dimensional such as a holographic record of a pneumatically-transported fiber.
The present invention also provides an efficient apparatus and method for monitoring the properties of fluid entrained entities. Such monitoring may be for independent direct measurements or for correlation with data from other instruments for the purpose of mutually verifying data or calibrating one of the instruments.
In accordance with the present invention, a physical map is produced by depositing fluid entrained entities, such as cotton fibers, trash and neps, in a pattern on a surface, such as a nylon mesh surface. When used with another instrument, preferably each position in the pattern is uniquely associated with data produced by the other monitor so that for a particular set of data one may locate on the physical map the entities that produced the data. This represents a topological mapping between the data event map and the physical map.
To produce the physical map of the preferred embodiment, an appropriate filter is interposed in an airstream containing entities and is moved relative to the airstream in a pattern at a known speed. Thus, the entities are deposited in a pattern on a filter.
In the preferred embodiment, a physical map apparatus is incorporated into an AFIS device. In such combination, an entity sample is fed into a separator that separates and individualizes the various entities in the sample and the individual entities are transported in a conduit by a vacuum driven airstream to an optical measuring station where characteristics of the entities are optically measured and optical data events are produced. From the optical station, the entities are carried by suction through a conduit to the physical map apparatus where a nozzle directs the entities through an appropriate filter. A suction tube, positioned on the opposite side of the filter from the nozzle, draws air from the nozzle and a suction pump is connected to the suction tube for providing the needed suction. As air passes from the nozzle, through the filter and into the suction tube, entities are caught by and deposited on the filter. Hereafter, the terms physical map and filter map are used interchangeably.
A drive mechanism is connected to move the mesh filter relative to the nozzle in a pattern to thereby deposit entities in such pattern on the filter and create a filter map.
A computer is connected to receive and record optical data produced by the optical measuring station as a function of time and it is also connected to record the position of the nozzle relative to the filter as a function of time. In this manner, a time-stamped map is produced on the filter. A correction factor indicative of the time that it takes for the entities to travel from the optical measuring station to the filter is provided to the computer and, using the correction factor, the computer correlates the optical data to positions in the pattern on the filter map. These correlated data are stored and selectively used or displayed.
Sensors are provided for sensing characteristics of the entities on the filter map as a function of map position. In a preferred embodiment, a first camera is positioned adjacent to the nozzle and a second camera is positioned adjacent to the suction tube. Stepping motors and translation tables drive the mesh filter in X, Y directions relative to the nozzle, the suction tube and the two cameras. A control system is provided between the computer and the stepping motors so that the computer precisely controls the position of the mesh filter, and the computer is provided with the position of the nozzle and the cameras. With this information, the computer is programmed to control the stepping motors and cause the filter to move in a reversing raster scan so that parallel rows of entities are deposited on the filter. Also, the computer is programmed to move the rows of entities into view of the cameras as desired. Preferably, the cameras are positioned relative to the nozzle to view two rows behind the nozzle as the entities are being deposited on the filter. Thus, as the entities are being deposited, the cameras are viewing a previously deposited row. In this manner, the process of depositing rows of entities also functions to scan the rows with the cameras. As the cameras scan, a series of video images are stored in the computer and are correlated to the map position that the cameras viewed, and it will be recalled that the stored optical data is also correlated to the map positions. Thus, the optical data, the map positions, and the video images are all cross-correlated and each may be output as a function of the others.
In another embodiment, the filter map is a circular cylinder and a helical pattern is produced.
Of course, the video or other measurements may be made at a later time since the physical map may be retained permanently.